Polycarbonate

Polycarbonate (PC) is a high-strength thermoplastic polymer known for exceptional durability, toughness, and impact resistance. It is one of the most resilient transparent materials available — up to 200× stronger than glass and significantly more robust than common acrylic plastics. Polycarbonate is one of the best materials for protective optic covers. It is extremely durable, lightweight, transparent, and reliably protects optics from damage even when hit by high-power airsoft guns. For this reason, it is the standard choice for most professional airsoft lenses, goggles, and optic shields.

Why is polycarbonate used in military equipment?

Extreme impact resistance:
Withstands hits that would shatter glass or most plastics.
Low weight:
Lightweight, perfect for helmets, shields, protective eyewear and optic hoods.
Optical clarity:
Excellent visual transparency — suitable for visors, ballistic windows, and optic covers.
Resistance to temperature and UV:
Ideal for military use in extreme conditions.

Why are polycarbonate covers used on red dots and riflescopes in airsoft?

They protect the lens from direct hits:
A polycarbonate cover can stop a BB that would otherwise shatter the optic’s lens (even expensive optics).
They are transparent:
The cover does not distort the image, so aiming remains accurate.
Cheap to replace:
If damaged, the cover is easily replaced — the optic stays intact.
Lightweight and universal:
Usable on red dots, riflescopes, and magnifiers.

What BB energy in Joules can polycarbonate withstand?

It depends on thickness, typically 2–3 mm. Tests show roughly:

2 mm polycarbonate:
Resists approx. 2–3 J (standard AEGs, DMRs up to ~2.5 J).
3 mm polycarbonate:
Holds up to 4–5 J (strong DMR/sniper replicas firing heavy BBs).
Ballistic PC shields (special blends):
These have significantly higher resistance, but they are a different category of material.

In practice, this means that a standard airsoft cover reliably stops a direct hit from any regular AEG or GBB rifle and usually even from a powerful DMR.